Sling tripping device



J. J. EAVES 3,050,328

SLING TRIPPING DEVICE Filed Oct. 15, 1960 Aug. 21, 1962 INVENTOR.

JAMES J. EAVES ilniteni rates fpatcnt @ffice 3,650,328 Patented Aug. 21,1962 3,056,328 SLING TRIPPING DEVICE James J. Eaves, Louisville, Missassignor to Taylor Machine Works, Louisville, Miss. Filed Get. 13, 1960,Ser. No. 62,456 Claims. (Cl. 29475) This invention relates to astripping or actuating device for releasing the load from load carryingslings, and is particularly adapted for use with machines for handlingpulp wood and other packaged wood products.

Other types of tripping mechaninsms have heretofore been contemplated,some hydraulic and some mechanical. A completely hydraulic type hascertain disadvantages, among them being that the load is carried by thehydraulic device which necessitates its being large and expensive. Also,the full hydraulic type cannot release both slings at the exact samemoment which causes undesirable conditions, such as the wood falling endfirst. An example of a completely mechanical type is the tripping devicedisclosed in my co-pending application, Serial No. 50,218, filed August17, 1960. In said co-pending application the elongated trip member waseffectively shortened to release the load upon subsequent upwardmovement of the tripping device. However, the present invention is acombination mechanical and hydraulic type of device which operates on adifferent principle than the device of my said co-pending applicationand instead of shortening the trip member, the load slings areeffectively lengthened.

The present invention is directed towards overcoming the disadvantagesof previous types of tripping mechanisms and towards providing newadvantages not present in the device of my said co-pending applicationor in any heretofore known device.

Thus, one of the objects of the present invention is to provide animproved device for releasing the load from load carrying slings.

A further object is to provide such a device that is adapted to releasethe load in mid-air, if so desired.

A further object is to provide such a device that is adapted to releasethe wood being loaded on a car or the like without lowering the carriageof the handling equipment low enough to give slack in the slings, thussaving much upward and downward travel of the carriage on the mast ofthe handling equipment.

A further object is to provide such a device that is adapted to causethe connecting means of the slings to respectively disconnectsimultaneously, allowing the wood to stay reasonably straight on thecar.

A further object is to provide such a device having a unique arrangementof the mechanical and hydraulic parts so that the hydraulic device doesnot take the weight of the load, thereby permitting a smaller and lessexpensive hydraulic device.

A further object is generally to improve the design and construction oftripping devices.

The means by which the foregoing and other objects of the presentinvention are accomplished and the manner of their accomplishment willbe readily understood from the following specification upon reference tothe accompanying drawings, in which:

FIG. 1 is a fragmentary front elevational view of the tripping device ofthe present invention with the device being shown in a position forcarrying a load, and with the jack cylinder being broken away forpurposes of illustration.

FIG. 2 is a portion of the structure shown in FIG. 1 but with aninter-mediate position of parts of the device being shown in dottedlines and with the parts being shown in solid lines just before thedevice is tripped.

FIG. 3 is a view similar to FIG. 2 of the device after being tripped.

FIG. 4 is a fragmentary view of a portion of the hook means shown inFIG. 1, but with the hook means being shown in 21 released position.

FIG. 5 is a fragmentary sectional view taken as on the line V-V of FIG.2, with a part being broken away for purposes of illustration.

FIG. 6 is a view on a reduced scale of the tripping device shown used inconjunction with wood handling equipment.

FIG. 7 is a sectional view taken as on the line VII-VII of FIG. 3.

Referring now to the drawing in which the various parts are indicated bynumerals, it is contemplated that the tripping device 11 be used withany suitable machine adapted to carry a load. For example, a typicalmachine with which the device 11 is adapted to be used is shown in FIG.6 wherein it will be seen a wood handling ma: chine 13 includes aself-propelled wheeled vehicle 15 having a mast 17 adjacent the forwardpart thereof upon which is slidably mounted a carriage 19 adapted to bemoved upwardly and downwardly along mast 17 to raise and lower the loadA, which is illustrated in this figure as pulp wood. Also, in the usualmanner mast 17 is adapted to be power actuated to tilt the mastforwardly or reanvardly. Carriage 19 adjacent the upper end thereof hasa suitable supporting structure 21 for tripping device 11, whichstructure includes a substantially horizontal platform 23.

A plate-like rocker arm 25 is rockably supported from structure 21adjacent one end thereof as at a substantially horizontal pivot axis 27.The means for rockably supporting rocker arm 25 preferably includes astationary tubular hinge portion 29 attached to platform 23 as bywelding or the like, a pair of outer hinge portions 31 fixedly attachedadjacent the lower ends of the spaced depending legs 33 of rocker arm25, and a hinge pin 35 extending through hinge portions 29, 31 andfixedly held in place by means of set screws 37 extending through hingeportion 29 and contacting the hinge pin.

A pair of slings 39, 41 are respectively pivotally coupled adjacent oneend to opposite sides of rocker arm 25 adjacent the distal end of therocker arm as at coupling axis 42, and the slings are respectivelycoupled adjacent the opposite ends thereof to supporting structure 21adjacent the opposite end of the supporting structure from rocker arm25.

Slings 39, 41 are substantially identical in construction and function,and the following description of sling 39 and its relationship to theother parts is deemed sufl'icient:

Sling 39 comprises, in general, two parts: a sling member 43 and anopposing sling member 45, which are detachably connected together byconnecting means, later to be described, to complete the sling. Theactual part of sling 39 that is coupled to rocker arm 25 as hereinabovedescribed is the upper end of sling member 43 which is coupled to thearm by suitable means and preferably comprises the following: a rod 47is fixedly attached along the upper edge of rocker arm 25 as by weldingor the like and extends beyond the opposite edges thereof. On oneextension of rod 47 past the edge of rocker arm 25 is rotatably receiveda sleeve 49 held thereon against accidental removal by means of a washer51 and cotter pin 53'. A depending member 55 is fixedly attached tosleeve 49 and is provided with an apertore through which extends ashackle 57 that completes the coupling of sling member 43 to the rockerarm 25. Sling 41 is coupled in a similar manner on the opposite side ofrocker arm 25. The actual portion of sling 39 that is coupled tosupporting structure 21 as heretofore I in this figure.

described is the upper end of opposing sling member which is preferablycoupled to the supporting structure as by means of a plate 59 attachedto the supporting structure as by welding or the like and provided withan aperture through which shackle 61 extends to complete the coupling ofthe sling member 45 to the supporting structure 21. Sling member 43 ispreferably constructed by a chain portion 63 forming the upper partthereof, and a cable portion 65 forming the lower part thereof, which isconnected by suitable means to the lower end of the chain portion.Likewise, sling member 45 comprises an upper chain portion 67 and alower cable portion 69. The lower end of cable portion 69 is providedwith a loop 71 adapted to be engaged in the manner shown in FIG. 1, by ahook pivotally mounted on cable portion 65 by a loop 75 provided in theend of the cable portion extending through an aperture 77 provided inhook 73.

An elongated trip member, indicated in general as at 79, is attached tohook 73 adjacent the opposite end of the hook from the pivotalconnection with loop 75. This connection of the trip member 79 and thehook 73 is preferably by means of a loop 81 provided in the end of tripmember 79 which extends through an aperture 83 in the hook. As in thecase of the sling members, trip member 79 is preferably formed with alower cable portion 85 and an upper chain portion 87. The upper end oftrip member 79 is fixedly anchored to supporting structure 21 as at 91by suitable means. A trip member 94 is also provided for sling 41 and isof the same construction and operation as trip member 79. Trip member 94is attached to supporting structure 21 in the same manner as trip member79, but preferably on the opposite side of the supporting structure.

A support 95, preferably in the form of a triangular plate, is fixedlyattached on one side of rocker arm 25 and extends perpendicular thereto.If desired a pair of these plates 95 may be provided in spacedrelationship for added structural strength. The lower edge or heel 97 ofplate 95 is adapted to contact the upper face of supporting structure 21to limit clockwise movement, as viewed in FIG. 1, of rocker arm 25 andis adapted to support the rocker arm in a first position as best seenThe relationship of heel 97 and rocker arm 25 is such that an angle isformed therebetween which is less than degrees so that the platesupports the rocker arm in said first position which is tilted to oneside (the right side as viewed in FIG. 1) of an upright dead centerposition of the rocker arm. This position shown in FIG. 1 is the loadcarrying position and it will be understood that the weight of the loadnormally urges heel 97 against supporting structure 21 and keeps rockerarm 25 in said first position.

A double acting hydraulic jack 99 is provided for pivoting rocker arm25. Jack 99 comprises the usual jack cylinder 101, piston 103 slidablymounted in the cylinder, and the usual piston rod 105 connected topiston 103 and extending outwardly through the end of jack cylinder 101.Suitable and well-known fluid supply means, not shown, and suitable andwell-known control means, not shown, are provided for introducing fluidto jack 99 through conduits 107, 109 for actuating the hydraulic jack ina well-known manner. Rod 105 is pivotally coupled to rocker arm 25 bysuitable means, as by a lug 111 fixedly attached to the rocker arm andby a pin 113 extending through aligned apertures in the lug and rod. Theopposite end of jack 99 from rocker arm 7 25 is pivotally connected to asliding base 115 of a mounting mechanism 117 for the jack. Thisconnection be tween jack 99 and base 115 is preferably by means of a pin119 extending through aligned apertures in a stud 121' fixedly attachedto jack cylinder 101 and through an upstanding bracket 123, which inturn is fixedly attached to base 115. Sliding base 115 is preferablyblocklike in construction and is provided with an opening 125 extendingtherethrough. Base 115 is slidably mounted on a rod 127 with the rodextending through opening 125 and with the rod being supported inhorizontal spaced relationship above platform 23 by means of sleeve-likestop members 129, 131 which are disposed on rod 127 adjacent oppositeends thereof. Stop members 129, 131 are fixedly mounted on platform 23and are respectively provided with set screws 133, 135 which engage rod127 and hold it fixed in place.

For the purposes of describing the operation of device 11, thedescription is started with the device in the position shown in FIGS. 1and 6. It is assumed that the slings 39, 41 are carrying a load Atherein which is suspended in the air. If it is desired to release theload in mid-air the hereinafter described sequence of operations isperformed with supporting structure 21 held in place. Otherwise, if itis desired to lower the load onto a car or the like supporting structure21 is lowered, as for example by lowering carriage 19 in the typicalwood handling machine 13 shown in FIG. 6. After the load is lowered ontothe car or the like then said following hereinafter described sequenceof operations is performed:

Jack 99 is actuated to cause the jack to extend to a first extendedposition shown in dotted lines in FIG. 2. Durin extension of jack 99from the retracted position shown in FIG. 1 to said first extendedposition rocker arm 25 will remain stationary to hold the end of pistonrod 1115 stationary and the jack will cause base 115 to move from aposition adjacent stop member 129 to a position in abutment with stopmember 131. Continued extension of jack 99 will cause rocker arm 25 tobe pivoted counterclockwise past the dead center position shown in solidlines in FIG. 2 until the jack is in a second extended position slightlypast the dead center position at which position it will be understoodrocker arm 25 will be unsupported against pivoting, whereby the weightof the load will cause downward pivot of the rocker arm in acounterclockwise direction as viewed in FIG. 2. This downward pivotingmovement is limited by a rubber bumper 137 which is fixedly attached tosupporting structure 21 and contacts the rocker arm to stop it in aposition in which the coupling axis 42 is below the levelit occupiedwhen rocker arm 25 was in said first position shown in FIG. 1; and, ifdesired, another rubber bumper 138 may be provided on the supportingstructure for cylinder 101. In other words, one of the upper ends ofslings 39, 41 are respectively lowered relative to supporting structure21 and thus the slings are respectively lengthened relative to tripmembers 79, 94 so that a pull is exerted on the trip members to releasethe load. Both of the trip members 79, 94 operate simultaneously and inthe same manner so that the following description of the operation oftrip member 79 will suifice:

When a pull is exerted on trip member 79, book 73 is rotated clockwisefrom the position shown in FIG. 1 about loop 75 to the position shown inFIG. 4 so that the hook releases loop 71 and the sling members 43, 45are disconnected. In the above described operation of tripping device11, it will be understood that after jack 99 has reached said secondextended position that no more power is needed from the jack but ratherthe jack 7 is pulled by rocker arm 25 and the weight of the load causesthe pivoting of the rocker arm. Also, it will be understood that jack 99is free to be pulled as above described since base 115 is free to slideto the left on rod 127 to a position adjacent stop member 129, as shownin FIG. 3. The tripping device 11 is re-set in position for the loadsimply by actuating jack 99 to retract the jack so that rocker arm 25 ispulled up into the position shown in FIG. 1.

From the foregoing description it will be understood that a very uniquetype of device is provided which offers many advantages over heretoforeknown types of tripping devices. In addition, it will be understood thatvery little power is needed by the jack 99 to push the rocker arm 25over the dead center position and thus, there is no necessity for alarge and expensive jack. Thus, it can be seen that the jack at no timesupports the load and due to the unique mounting arrangement the Weightof the load exerts no force on the jack when it is free falling beyondthe dead center position.

Although the invention has been described and illustrated with respectto a preferred embodiment thereof, it is to be understood that it is notto be so limited since changes and modifications may be made thereinwhich are within the full intended scope of this invention ashereinafter claimed.

I claim:

1. In a load carrying apparatus, a supporting structure, a trippingdevice comprising a rocker arm rockably supported from said structure ata pivot axis, sling means for carrying a load, said sling meansincluding at least a pair of sling members each having an upper end anda free end, one of said sling members being coupled adjacent its upperend to said structure and the other of said sling members beng coupledadjacent its upper end to said rocker arm at a coupling axis spaced fromsaid pivot axis, connectng means detachably connecting the free ends ofsaid sling members to releasably hold the load, an elongated trip memberattached adjacent one end thereof to said connecting means and adaptedto be pulled, said trip member being coupled adjacent the opposite endthereof to said structure, said connecting means including means fordisconnecting said connecting means when said trip member is pulled,means supporting said rocker arm in a first position tilted to one sideof an upright dead center position of said rocker arm, mounting meanscarried by said structure; said mounting means including a rod, a baseslidably mounted on said rod, a first stop member mounted on said rodadjacent one end thereof and a second stop member mounted on said rodadjacent the opposite end thereof; jack means coupled adjacent one endthereof to said rocker arm and coupled adjacent the opposite end thereofto said base, said jack means being moveable between a retractedposition and extended positions, with said rocker arm in said firstposition extension of said jack means from said retracted position to afirst extended position being effective to cause said base to slide froma first position adjacent said first stop to -a second position adjacentsaid second stop, with said base in said second position furtherextension of said jack means beyond said first extended position to asecond extended position being effective to pivot said rocker arm in onedirection from said first position of said rocker arm past said deadcenter position to an unsupported position so that the weight of theload carried by said sling means is adapted to cause downward pivot ofsaid rocker arm, said rocker arm being pivotable far enough downwardlyin said one direction to carry said coupling axis below the level itoccupied when said rocker arm was in said first position whereby saidsling means is effectively lengthened relative to said trip member sothat a pull is exerted thereon to disconnect the connecting means andrelease the load, and pivot of said rocker arm in said one directionpast said dead center position being effective to pull therewith saidjack means as a unit and slide said base on said rod without said jackmeans carrying any of the load.

2. In a load carrying apparatus, a supporting structure, a trippingdevice comprising a rocker arm rockably supported from said structure ata pivot axis, sling means for carrying a load, said sling meansincluding at least a pair of sling members each having an upper end anda free end, one of said sling members being coupled adjacent its upperend to said structure and the other of said sling members being coupledadjacent its upper end to said rocker arm at a coupling axis spaced fromsaid pivot axis, connecting means detachably connecting the free ends ofsaid sling members to releasably hold the load, an elongated trip memberattached adjacent one end thereof to said connecting means and adaptedto be pulled, said trip member being coupled adjacent the opposite endthereof to said structure, said connecting means including means fordisconnecting said connecting means when said trip member is pulled,means supporting said rocker arm in a first position tilted to one sideof an upright dead center position of said rocker arm, mounting meanscarried by said structure, jack means coupled adjacent one end thereofto said rocker arm and coupled adjacent the opposite end thereof to saidmounting means, said mounting means establishing a movable amount forsaid jack means, means limiting movement of said opposite end of saidjack means in opposite directions so that said jack means is adapted tobe stopped in a first stopped position and a second stopped position,said jack means being movable between a retracted position and extendedpositions, with said rocker arm in said first position extension of saidjack means from said retracted position to a first extended positionbeing efiective to cause said opposite end of said jack means to movefrom said first stopped position to said second stopped position, withsaid opposite end of said jack means in said second stopped positionfurther extension of said jack means beyond said first extended positionto a second extended position being effectiv to pivot said rocker arm inone direction from said first position of said rocker arm past said deadcenter position to an unsupported position so that the weight of theload carried by said sling means is adapted to cause downward pivot ofsaid rocker arm, said rocker arm being pivotable far enough downwardlyin said one direction to carry said coupling axis below the level itoccupied when said rocker arm was in said first position whereby saidsling means is eifectively lengthened relative to said trip member sothat a pull is exerted thereon to disconnect the connecting means andrelease the load, and pivot of said rocker arm in said one directionpast said dead center position being effective to pull therewith saidjack means as a unit without said jack means carrying any of the load.

3. In a load carrying apparatus, a supporting structure, a trippingdevice comprising a rocker arm rockably supported from said structure ata pivot axis, s-ling means for carrying a load, said sling meansincluding at least a pair of sling members each having an upper end anda free end, one of said sling members being coupled adjacent its upperend to said structure and the other of said sling members being coupledadjacent its upper end to said rocker arm at a coupling axis spaced fromsaid pivot axis, connecting means detachably connecting the free ends ofsaid sling members to releasably hold the load, an elongated trip memberattached adjacent one end thereof to said connecting means and adaptedto be pulled, said trip member being coupled adjacent the opposite endthereof to said structure, said connecting means including means fordisconnecting said connecting means when said trip member is pulled,means supporting said rocker arm in a first position tilted to one sideof an upright dead center position of said rocker arm, mounting meanscarried by said structure, jack means coupled adjacent one end thereofto said rocker arm and coupled adjacent the opposite end thereof to saidmounting means, said jack means being extendable to pivot said rockerarm from said first position past said dead center position to anunsupported position so that the weight of the load carried by saidsling means is adapted to cause downward pivot of said rocker arm, saidrocker arm being pivotable far enough downwardly in said one directionto carry said coupling axis below the level it occupied when said rockerarm was in said first position whereby said sling means is effectivelylengthened relative to said trip member so that a pull is exertedthereon to disconnect the connecting means and release the load.

4. In a load carrying apparatus, a supporting structure, a trippingdevice comprising a rocker arm rockably supported from said structure ata pivot axis, sling means for carrying a load, said sling meansincluding at least a pair of sling members each having an upper end anda free end, one of said sling member being coupled adjacent its upperend to said structure and the other of said sling members being coupledadjacent its upper end to said rocker arm at a coupling aXis spaced fromsaid pivot axis, connecting means detachably connecting the free ends ofsaid sling members to releasably hold the load, an elongated trip memberattached adjacent one end thereof to said connecting means and adaptedto be pulled, said trip member being coupled adjacent the opposite endthereof to said structure, said connecting means including means fordisconnecting said connecting means When said trip member is pulled,means supporting said rocker arm in a first position tilted to one sideof an upright dead center position of said rocker arm, mounting meanscarried by said structure, said rocker arm being pivotable from saidfirst position past said dead center position to an unsupportedposition, means connected to said rocker arm for pivoting said rockerarm from said first position past said dead center position to saidunsupported position so that the weight of the load carried by saidsling means is adapted to cause downward pivot of said rocker arm toeffectively lengthen said sling means relative to said tripping memberand disconnect said connecting means.

5. In a load carrying apparatus, a supporting structure, a trippingdevice comprising a rocker arm rockably supported from said structure ata pivot axis, a pair of slings for carrying a load, each of said slingsincluding at least a pair of sling members each having an upper end anda free end, one of said sling members of each of said slings beingcoupled adjacent its upper end to said structure and the others of saidsling members of said slings being respectively coupled adjacent theopposite ends thereof to said structure, a pair of connecting meansrespectively detachably connecting the free ends of said pairs of slingmembers to releasably hold the load, a pair of elongated trip membersrespectively attached adjacent one of the ends thereof to said pair ofconnecting means and adapted to be pulled, said pair of trip membersbeing respectively coupled adjacent the opposite ends thereof to saidstructure, said pair of connecting means respectively including meansfor disconnecting said connecting means when said trip members arepulled, means supporting said rocker arm in a first position tilted toone side of an upright dead center position of said rocker arm, saidrocker arm being pivotable from said first position past said deadcenter position to an unsupported position, means connected to saidrocker arm for pivoting said rocker arm from said first position pastsaid dead center position to said unsupported position so that theweight of the load carried by said pair of slings is adapted to causedownward pivot of said rocker arm to effectively lengthen said pair ofslings relative to said pair of tripping members and simultaneouslydisconnect said pair of connecting means.

References Cited in the file of this patent UNITED STATES PATENTS617,267 Wiley Jan. 3, 1899 r ew

